KR20170128478A - How to apply hydrographic film to articles - Google Patents

Abstract

The present invention is based on the idea that a hydrographic film is applied to a polymer material or the like to improve aesthetic appeal. Such as a plastic closure. The invention also relates to a method of applying a coating with a hydrographic film ink to an article such as a plastic closure, wherein the method does not dry the ink first and thus keeps the ink in a fluid state, And preferably avoids the time consuming and sometimes problematic steps of drying and reactivating the hydrographic film inks.

Description

How to apply hydrographic film to articles

relation Cross reference to application

None

Federal sponsorship research or development

None

Microfiche / Copyright reference

None

Technical field

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to articles such as plastic closures molded with a polymeric material for use in conjunction with an associated container for packaging beverages, foods, and the like, and more particularly to articles such as patterned hydrographic To a molded plastic article such as a closure coated with a film. The present invention also relates to a technique for applying a coating to an article such as a plastic closure, and more particularly to a method of coating an article with hydrographic film ink, wherein the method does not dry the ink first, To avoid the time consuming and sometimes problematic steps of applying ink to the articles in the water tank, preferably drying and reactivating the hydrographic film inks.

Plastic closures molded from polymeric materials, including polypropylene, polyethylene, copolymer blends and other olefin polymers, are commercially available for use with related containers for packaging carbonated and non-carbonated beverages, food products, non- It was very successful. This type of closure, which can be suitably formed by compression or injection molding, typically includes a female threaded portion to threadably engage the male threaded portion of the associated container. Such closure may be desirable to be configured to provide effective and reliable tamper-evidence to the consumer.

To enhance the aesthetic appeal of this type of molded plastic closure, a dye or colorant may be incorporated into the polymer composition forming the closure. Conventionally, the overall appearance of such closures is typically determined by the components of the molded polymer, and by any pigment or coloration of the polymer material. To a limited extent, graphics may be applied to closures molded by ink transfer or inkjet printing, but such printing is generally limited to providing characters or simple graphics to closures.

More recently, hydrographic printing technology has developed and is applied to the surface of an article such as a closure in which printed hydrographic film ink is molded. With this technique, various graphics that are not actually limited can be applied to the closure without adversely affecting the sealing and tamper-evidence capabilities of the closure. This technique typically involves applying the ink to a film carrier formed of water soluble polyvinyl alcohol (PVA). This type of film material, such as those often used in detergent bags, breath-freshness strips, etc., dissolves within about 60 seconds, typically upon contact with water, so that application to the article to be coated Leaving the decorative ink printed on the film for further processing.

Conventionally, a typical process of applying hydrographic to closures and other articles involves printing the hydrographic film with ink followed by drying the ink. For application, the ink side of the dry film is rewet with a solvent (often referred to as reactivation) and floats on the surface of a deep tank that retains the water tank into which the article is introduced for coating. After the film is dissolved, the article is moved downward through the ink supported on the surface of the water tank, whereby hydraulic pressure acts to apply the hydrographic ink to the surface of the article. Since typical inks are inherently hydrophobic, wetting of the product is avoided before the product is introduced downward into the water tank through the ink layer.

To date, hydrographic films have generally been produced by gravure printing, which is advantageous in that the prints can be carried out at a relatively high speed and thereafter the film is dried, then rolled and applied to the article . However, customization is somewhat limited in that a new gravure roll must be manufactured for any desired change in the pattern being produced. In addition, water-soluble films are typically printed on a four to nine color gravure printing press, which requires film unwinding, printing, drying and winding for each color. The gravure rolls transfer the ink through the contact of the film with the surface energy, and in this process complete drying of each additional color is essential.

Non-contact inkjet printing techniques have also been used to produce hydrographic films, and the digital nature of the printing process facilitates customization. However, the demand step of drying the printed film before introduction into the bath reduces the efficiency of the coating process. The linear process speed for coating is typically much higher than the linear speed at which the film can be digitally printed and dried. Digital printers typically operate at 1.1 linear feet per minute or less while a water transfer printing process typically operates at a speed of 4.0 linear feet per minute or more, resulting in a processing inconsistency of 2.9 linear feet per minute And undesirably forms " bottlenecks " in the coating of the article, interfering with " inline " processing and coating of the article. In addition, the requisite reactivation of the ink of the film can sometimes be a problem, because, besides the cost of the activator solvent, there are cases of insufficient or excessive use of the activator solvent and of the non-uniform distribution of the solvent.

The present invention overcomes the disadvantages associated with coating conventional articles with hydrographic film inks by performing coatings without drying the film inks to maintain the ink in an activated state and thereby reducing inefficiencies and problems associated with ink reactivation, .

According to the present invention, the method of coating a plastic closure allows for the application of the patterned hydrographic film to each individual molded plastic closure. This type of hydrographic film can be provided in virtually unlimited variety of patterns and configurations, including grain, fabric, animal print and similar patterns. A novel or abstract pattern can also be applied. It is possible to improve the visual appeal of such packaged products by adopting patterns in the form of real images of the products in related containers and closure packages. Graphic patterns can include commercial or sporting logos, etc., adding to the charm of such closure and even giving the molded closure product quality worthy of collection.

The present invention relates to a method of coating an article such as a plastic closure in a hydrographic fashion, which method facilitates efficient and cost-effective processing. In particular, the method of the present invention is based on the fact that a hydrographic film applied to one or more articles without first drying the ink to form the film is introduced into the water tank, thereby exploiting the wettability of the film ink to be newly printed as ink transfer means . This not only leads to significant time savings and improved processing flexibility, but also avoids the cost of conventional active solvents that are problematic with inadequate solvent application.

According to one aspect of the present invention, a method of coating a plastic closure includes providing a plastic closure having a circular top wall portion and an annular skirt portion suspended in the top wall portion. The annular skirt portion may be provided with a female thread forming portion cooperatively threaded with the male thread forming portion of the associated container, which together provide an appropriate package for the contents of the container. The method of the present invention further contemplates the steps of providing a patterned hydrographic film and applying the patterned hydrographic film to the outer surface of the closure to form a coated plastic closure. The outer surface of the closure includes an upper wall portion and an outward surface of the annular skirt portion.

To improve the aesthetic and tactile appeal of a coated plastic closure, the coated plastic closure can be textured. It is contemplated that such texturing may be performed by texturing the outer surface of the closure prior to applying the patterned hydrographic film. Alternatively or additionally, the patterned hydrographic film can be textured to provide a coated plastic closure having the desired texture.

According to another aspect of the invention, a method of coating an article comprises providing at least one article to be coated, each article having at least one surface to be decorated. The method further comprises printing the film with ink and delivering the printed film to a surface of a fluid container, typically a deep water tank. In particular, the film is preferably delivered without drying the ink that prints the film.

The method further contemplates dipping one or more articles in a fluid container to apply the hydrographic film ink to the surface of each article to be decorated. Accordingly, the present invention contemplates that the drying step of a conventional coating process is avoided, since the ink remains active for a sufficient time to effect transition to the article, thereby activating the activation step in the process It removes it. After immersion, the one or more coated articles are dried and / or cured as required to achieve the desired coating durability.

In another aspect of the invention, the printing and delivery steps are controlled and adjusted, preferably promoting processing efficiency. According to the present method, the ink remains in the fluid state and is applied to the article without further activation of the ink.

Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims.

FIG. 1 is a partial side elevation view of a container with a closure - a hydrogel applied in accordance with the present invention -
Figure 2 is a perspective view of a closure coated with hydrographic according to the present invention,
Figure 3 is a perspective view of another closure applied with hydrographic according to the present invention,
Figure 4 is a perspective view of another closure applied with hydrographic according to the present invention,
Figure 5 is a perspective view of another closure coated with hydrographic according to the present invention,
Figure 6 is a flow chart illustrating the steps of a method for providing hydrographic on a bath,
Figure 7 is a flow chart illustrating steps of another method of providing a hydrographic film on a water bath.

While the invention is susceptible of embodiment in various forms, there are shown preferred embodiments of the invention in the following description of preferred embodiments, which are regarded as illustrative of the invention and are not to be construed as limiting the invention to the particular embodiment But is not intended to be limiting.

Figures 1-5 illustrate various embodiments of coated plastic articles in the form of closure 10 that implement the principles of the present invention. As illustrated in various embodiments, each coated plastic closure 10 includes an annular top wall portion 12 and an annular skirt portion 14 suspended in the top wall portion 12. By virtue of the generally cylindrical configuration of the closure 10, each closure forms a vertical axis extending through the center of the top wall 12.

A patterned hydrographic film 20 is applied to the outer surface of the closure 10 including the top wall 12 and the outwardly facing surface of the annular skirt 14. The pattern of the hydrographic film 20 is a physical feature of the closure such as the vertical axis of the closure, at least one of the upper and lower edges 14a and 14b of the annular skirt portion 14, Lt; / RTI >

The drawings illustrate various types of patterned hydrographic films that can be applied to a coated plastic closure 10. Such a pattern may include a grain (Fig. 5), a fabric pattern (Fig. 4), an animal print pattern (Fig. 2) or other unrealistic or natural patterns. In the embodiment illustrated in FIG. 3, the pattern includes discrete graphic elements 22, such as commercial or sport logos, which may be placed on the closure 10, such as by substantial alignment with the physical features of the closure, So that the graphic element 22 is centered relative to the top wall portion 12 of the closure. It is contemplated that in this particular embodiment, the sports theme graphic element 22 may be provided in association with a suitable pattern, such as a leather-like pattern similar to a basketball for use in association with a basketball team logo. It is contemplated that the hydrographic film may be formed to represent the contents of the relevant closures and container packages or to include a photorealistic pattern of food on such contents. As will be appreciated, such sensory patterns highly favorably enhance the aesthetic appeal of such packaging.

Techniques for applying hydrographic films to related molding plastic closures are known. Generally speaking, the patterned hydrographic film is suspended or suspended in a water tank, and the individual plastic closures are generally immersed in the water tank through the hydrographic film, whereby the hydrographic film is applied to the outer surface of the closure. By immersing each closure in a predetermined relationship to the associated hydrographic film, the pattern of the hydrographic film can be adjusted for the physical features of the closure.

A typical method of applying a hydrographic film to an article comprises the following steps:

1) Printed PVA (polyvinyl alcohol) is placed into the hot water tank with the PVA side down;

2) hot water dissolves the PVA layer leaving only the hydrophobic ink layer;

3) " Active " is sprayed on the ink layer to soften the surface and promote bonding to the partial surface:

4) Most polyolefin parts are spray coated with a series of bonding promoters prior to immersion.

5) When the part is gently pushed through the water, the ink easily follows the surface of the part.

6) The activator acts as an adhesion agent between the ink forming the strong junction with the part.

7) After removal of the parts, water is sprayed, cleaned, heat dried and then transparent coated.

The steps of applying the hydrographic film to an article formed of a polyolefin such as high density polyethylene (HDPE) or polypropylene (PP) include application of an ether coating and a base coating prior to applying the hydrographic film to the article. Application of a hydrographic film to an article formed of an amorphous material, such as acrylonitrile butadiene styrene (ABS), typically does not take into account the step of applying an ether coating or a base coating.

It is contemplated that the method may be practiced to apply a coating to a wide range of articles. Although the present method identifies a particular application for applying a coating to a closure molded with a polymeric material, the present invention is applicable to coating a wide range of articles formed of metal as well as polymeric materials with hydrographic film inks. In order to coat the closure, it is contemplated to apply the hydrographic film ink to the outer surface of each closure, but in some applications the article may be formed of a transparent polymeric material and the coating applied to the inner surface to provide durability, abrasion resistance, It is conceivable that a desired decorative effect with improved resistance is provided.

Fig. 6 is a cross-sectional view of a water tank according to a known technique that may be employed to practice the present invention, including providing at least one article to be coated, each article having at least one surface to be decorated. Fig. 3 is a flow chart illustrating a method for preparing a hydrographic film. Fig.

According to another aspect of the invention illustrated in Figure 7, the method further comprises printing the film with ink and delivering the printed film to a surface of a fluid container, typically a deep water tank. In particular, the film is preferably delivered without drying the ink that prints the film.

The method further contemplates the step of dipping one or more articles in a fluid container so that the hydrographic film ink is applied to the surface of each article to be decorated. This aspect of the present invention therefore contemplates that the drying step of a conventional coating process is avoided because the ink remains active for a sufficient period of time to effect the transition to the article, . After immersion, the one or more coated articles are dried and / or cured as required to achieve the desired coating durability.

In another aspect of the invention, the printing and delivery steps are controlled and adjusted, preferably promoting processing efficiency. According to the present method, the ink remains in the fluid state and is applied to the article without further activation of the ink.

Thus, this aspect of the invention preferably solves the digital print speed limitation associated with existing techniques associated with the required drying process, increasing the processing speed from 1.1 linear feet per minute to up to 11.1 linear feet per minute, The reason is that the wet ink remains in a desirable state for processing. The method also preferably eliminates the need for conventional ink activation steps of conventional processes. In addition, taking into account the importance of strict environmental health and safety (EHS) regulations, elimination of the activation phase facilitates the fulfillment of requirements to provide explosion protection while reducing respiratory concerns.

This aspect of the invention also preferably eliminates the additional cost of ink rewetting through application of activator solvent. In particular, the print ink remains in its original wet state, i.e., the state ideal for application or coating for the article. Those skilled in the art know that one of the most troubling aspects of the male transcription is to the ink activation process, thereby eliminating the difficulty associated with ink activation (e.g., too much active agent, insufficient active agent, non-uniform active agent distribution) More consistent ink transfer can be achieved.

In particular, variations of this aspect of the invention contemplate applying decorative ink to the carrier film when the film is supported on a fluid surface of a fluid container such as a surface of a water tank in a deep tank. For this aspect of the invention, the carrier film is delivered to a fluid surface such as water, and then the ink is printed on the film as it is carried on the fluid surface. The article to be coated is then dipped down into the fluid container without drying the ink. The ink is then applied to the desired surface of each article to be coated. Much improved processing efficiency can be achieved, wherein the digital character of the inkjet printing process allows cost-effective customization of decorative coatings.

While the use of currently solvent based decorative inks is contemplated, alternate ink compositions such as ultraviolet curing inks can be advantageously employed within the scope of the present invention.

As mentioned above, control and regulation of the printing and coating processes are considered to maximize the efficiency of the overall processing. In this regard, for some applications it may be desirable to stretch or stretch the printed film while in the fluid container before introducing the article to be coated. This contributes to maximizing the efficient use of the hydrographic film.

Yes

Step 1: Transfer ink to film (film printing)

equipment

Printers: Digital Inkjet Printers

- Printing method: Valve Jetting, Drop-on Demand, Piezo Drive method

- Number of nozzles: (180 x 8 columns) x 1 head

- Minimum droplet size: 3.5 pl

- Number of printheads: 1 (CMYK)

- Head height: 1.5 mm / 2.5 mm

- Maximum print speed / resolution 600sqf / h / 360x360

- Maximum resolution: 1440 dpi

- Maximum media width: 64 "

Expendables

Ink: Pigment based on solvent carrier (45-55% ethyl lactate and 35-45% ethylene glycol monobutyl ether acetate mixture)

Medium: PVA water-soluble film (width 1 m, thickness 35 m)

Print

Printed film: Graphically printed PVA film with still wetted ink

Major printer settings

Print temperature: Ambient 68-72 ° F (not available for all conventional thermal curing processes)

Print resolution: 720x720 DPI

Color mode: CMYK variable dot

Print dither: SO diffusion

Print speed: 151 sq. Per hour. ft.

step

1. Make sure the ink and film are properly loaded in the printer

2. Loading the digital image into the applicable printer parameter adjustment software

3. Make sure the major print settings match those listed above.

4. Go to step 2

Step 2: Transfer film to part (dipping part)

equipment

Deep Tank: Open the upper water holding vessel (temperature controlled, stainless steel tank with filtering weir of 60 "x 120" x 36 "high)

Expendables

Printed film: Graphically printed PVA film with still wetted ink

Film Solubility: Water (Training water maintained at 80-90 ° F)

Part: Molded olefin closure

Print

Decorative parts: 3D exterior print closure

step

1. After digital inkjet printing, immediately cut the film in the printer

 Transfer the wet ink side to the deep tank

2. Immerse the parts into the surface of the film within 60 seconds of entering the tank

3. Remove parts from the tank

4. Cleaning the remaining PVA from the part

5. Drying parts

6. Parts are now fully decorated.

From the foregoing, it will be appreciated that many modifications and variations can be made without departing from the spirit and scope of the novel concept of the present invention. It is to be understood that no limitation is intended or should be inferred from the specific embodiments. This disclosure is intended to cover all such modifications as fall within the scope of the claims defined by the appended claims.

Claims (8)

As a coating method for an article,
Providing one or more articles to be coated, each article having one or more surfaces to be decorated;
Printing the film with ink;
Transferring the printed film to the surface of the fluid container, wherein the film is delivered without drying the ink printing the film; And
Immersing the plurality of articles in the fluid container and removing the articles from the fluid container to apply the ink to the surface of each article;
≪ / RTI > The method of claim 1, wherein the printing step and the delivering step are controlled and adjusted. The method of claim 1, wherein the ink is maintained in a fluid state, whereby the ink is applied to the article without further activation of the ink. The method of claim 1, wherein the one or more articles each comprise a closure molded from a polymeric material having a surface to which the ink is applied. The method of claim 1, wherein each of the one or more articles is dried and / or cured after immersion. 2. The method of claim 1, wherein each of the articles comprises a closure molded from a polymeric material and having a circular upper wall portion and an annular skirt portion suspended in the upper wall portion, Wherein the coating is an outer surface. As a coating method for an article,
Providing one or more articles to be coated, each article having one or more surfaces to be decorated;
Transferring the film to the surface of the fluid in the fluid container;
Printing ink on the film; And
Dipping the one or more articles in the fluid container without drying the ink printed on the film and removing the one or more articles from the fluid container to apply the ink to the surface of each of the one or more articles
≪ / RTI > 8. The article of claim 7, wherein each of the articles comprises a closure molded from a polymeric material and having a circular top wall portion and an annular skirt portion suspended in the top wall portion, Wherein the coating is an outer surface.

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